Pleat forming attachment for sewing machines

ABSTRACT

In a pleat forming attachment for sewing machines, the pleat forming head on which the pleat forming blades and channel are mounted is pivotally mounted to swing on a horizontal axis parallel to the planes of the blades. Means are provided for adjusting the depth of the pleats and for simultaneously adjusting the amplitude of pivotal movement of the head as the pleat is formed. Means are also provided for adjusting the spacing between successive pleats.

United States Patent [191 Block I [451 Apr. 9, 1974 PLEAT FORMING ATTACHMENT FOR SEWING MACHINES [75] Inventor: Charles Block, North Bellmore,

[73] Assignee: Gellman Industries, Inc., New York,

[22 Filed: May 31, 1972 [21] Appl. No.: 258,341

[52] U.S. Cl. 112/134, 112/144 [51] Int. Cl D05b 35/08 [58] Field of Search 112/132-136,

[56] References Cited UNITED STATES PATENTS 3,331,345 7/1967 Firestein et al, [12/146 X 2,669,955 2/1954 Gellman 112/136 3,010,621 11/1961 Bonarrigo 223/31 3,157,140 11/1964 Williams, Jr. 112/134 3,661,103 5/1972 Firestein et al.... 112/134 3,133,516 5/1964 Gorin et a1 112/132 Primary Examiner-Jordan Franklin Assistant Examiner-Peter Nerbun Attorney, Agent, or Firm-Sandoe, Hopgood &

Calimafde 57 ABSTRACT In a pleat forming attachment for sewing machines, the pleat forming head on which the pleat forming blades and channel are mounted is pivotally mounted to swing on a horizontal axis parallel to the planes of the blades. Means are provided for adjusting the depth of the pleats and for simultaneously adjusting the amplitude of pivotal movement of the head as the pleat is formed. Means are also provided for adjusting the spacing'between successive pleats.

9 Claims, 23 Drawing Figures PATENTEDAPR 9 m4 3,802,361

sum 2 or 6 QOE PATENTEUAPR 9 I974 SHEET 3 BF 6 F IG.6

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l PLEAT FORMING ATTACHMENT FOR SEWING MACHINES This invention relates to pleat forming attachments for sewing machines of the general type .shown and described in Gellman US. Pat. No. 2,669,955 and Firestein Pat. No. 3,331,345. A somewhat similar pleat forming attachment. is shown and described in bonarrigo Pat. No. 3,010,6211 In the Gellman and Bonarrigo patents the invention relates only to the pleat forming device. In the Fires'tein patent the pleat forming device is tied in with the sewing machine mechanism in such manner as to permit the automatic formation of pleats as the sewing operation proceeds.

Such machines are widely used for the forming and stitching of pleats along the upper edges of draperies and curtains. In the use of such machines it is necessary to provide a double line of stitching at the base of each of the pleats which extends inwardly from the upper edge of the fabric a predetermined distance, and a shorter double line of stitching at right angles thereto at the bottom of the pleats. Forthis purpose, the sewing machine is provided with a movable feed plate and a clamp mounted thereon which grips the fabric adjacent the pleat which is being stitched, and holds it while the feed plate is moved, under control of the sewing machine mechanism, in a pattern to move the fabric with respect to the reciprocating needle of the sewing machine to form the desired lines of stitching therein.

In such machines, it is desirable that the machine shall automatically form a succession of pleats of equal pleat depth which are spaced apart by equal predetermined distances from center to center. It is also desirable to be able to make adjustments in both pleat depth and pleat spacing as required to accommodate the design of the particular drape or curtain to be pleated. For example, to provide a drape with pleats one-half inch deep, spaced at distances 3 inches between centers would require'different adjustments than those required for pleats thre'e fourths inch deep spaced at distances 4 inches betweeen centers.

It is an object of this invention to provide means for making such adjustments easily and quickly.

In the operation of such machines, each of the pleats formed by the pleater is stripped from the pleater by hand by the operator and placed on the feed plate where it is gripped and held by the clamp while stitching proceeds. Therefore, in order to facilitate the work of the operator, it is of great importance that the pleater be so constructed and located with respect to the sewing machine as to make it possible for the operator to present the formed pleat to the sewing machine in proper relation to the needle with the exercise of minimum effort and skill. It is an object of this invention to do so.

Other objects and advantages of the invention will appear hereinafter.

A preferred embodiment of the invention selected for purposes of illustration is shown in the accompanying drawings, in which,

.FIG. 1 is a front elevation of a sewing machine with the attachment in place.

FIG. 2 is a top plan view of the pleater.

FIG. 3 is a side elevation of the pleater, partly in section on the line 3-3 of FIG. 2.

FIG. 4 is a section on the line 44 of FIG. 2

FIG. 5 is a top plan view of the pleater head with the adjustment cams removed.

FIG. 6 is a front elevation of the pleater head.

FIG. 7 is a section on the line 7-7 of FIG. 6.

FIG. 8 is an elevation of the adjustment cams.

FIG. 9 is an elevation of the adjustment cam assembly.

FIG. 10 is a section on the line 10--10 of FIG. 9.

FIG. 11 is a semi-diagrammatic plan view of the feed plate of the sewing machine.

FIGS. 12 and 13 are semidiagrammatic plan and elevation views, respectively showing the relationship between the pleater and the sewing machine at the beginning of an operating cycle.

FIGS. 14 and 15 are similar views at a later stage of the cycle showing the workpiece entering the pleater.

FIGS. 16 and 17 are similar views at a still later stage of the cycle showing the tilting of the pleater head as the pleater channel closes.

FIGS. 18 and 19 are similar views at a still later stage of the cycle showing the pleater channel fully closed and the pleater moved in to form slack in the workpiece.

FIGS. 20 and 21 are similar views at a still later stage of the cycle showing'the beginning-of the stripping of the workpiece from the pleater.

FIGS. 22 and 23 are similar views near the end of the cycle showing the workpiece with a completed formed pleat stripped from the pleater and held by the operator ready to be inserted into the sewing machine for the pleat to be stitched during the next cycle.

Referring to the drawings, the entire pleat forming unit is mounted on a swing plate 1 which is pivotally mounted on the base plate 2 by a pivot bolt 3, which said base plate, in turn, is mounted on a table top 4 on which the sewing machine may also be mounted. The sewing machine includes a movable feed plate 5 and clamp 6 to hold the workpiece, and the relation of the feed plate and clamp to the pleat former is at various stages of the operating cycle as shown in FIGS. 1] to 23. As shown in FIG 1 l, the feed plate is provided with an L-shaped slot through which the needle moves to form the L-shaped lines of stitching indicated by 8. The clamp may also be provided with a side gauge 9 and an adjustable back gauge 10 for aiding the operator in properly positioning the workpiece for sewing.

The pleat former as shown in FIGS. 2 to 6 comprises a pleater head 11 having an arm 12 extending laterally therefrom upon which is mounted a fixed center blade 13 and a pair of movable blades 14 and 15 which are mounted on opposite sides of the fixed blade and are hinged to swing on axes l6 and 17 parallel to the plane of blade 13. Blades 14 and 15 are normally held in open position as shown in FIG. 7 by springs 18.

Also mounted on head 11 and extending over the blades l3, l4 and 15 in position to cooperate therewith is a U-shaped pleater channel 20 which cooperates with the blades to form pleats in the manner hereinafter de scribed. Channel 20 is mounted on a cross bar 21 which is connected to piston rod 22 which extends into cylinder 23 by means of which the channel may be actuated.

' Guide rods 24 connected to the cross bar 21 extend side of the arm 12 to assist the operator in guiding the material to proper position for pleating.

It will be noted that the lower edges of the channel are parallel to the upper edges of the blades 13, 14 and 15. It will also be noted, however, that the axes of the piston rod 22 and the guide rods 24 are slightly inclined to a perpendicular to the edges of blades 13, 14 and 15. That is, the said axes and lines through said edges meet in at slightly obtuse angle. As a result, as the channel 20 moves downwardly to form a pleat, it moves sidewise slightly to exert a wiping or slicing action on the fabric which facilitates the formation of smooth and uniform pleats.

The swing plate 1 is normally biased in counterclockwise direction by spring 28 having one end attached to the swing plate 1 and the other end attached to the base plate to hold the swing plate against an adjustable back stop 29 mounted on the base plate 7. By loosening the bolts 30 to permit adjustment of the stop 29, the head 11 and the pleating blades may be brought into proper angular relationship to the feed plate 5. In the proper position of adjustment the blade 13 should be parallel with the long line of stitching 8 at the extreme counterclockwise position of the feed plate 5 as shown in H6. 18.

Referring now to FIG. 3, means are provided for connecting the pleater head 11, and its associated parts as previously described, to a pleater slide plate 31, said means comprising the L-shaped bracket 32 bolted thereto. The slide plate 31 and head 11 move together when actuated by the piston rod 33 of cylinder 34, the said piston rod being connected to the slide plate by angle 35 and connector 36. The cylinder is rigidly mounted on an adjustment plate 37 which is connected by pins 38 to guide members 39 having grooves 40 therein in which the slide plate 31 slides. Plate 37 is mounted to slide in grooves 42 of a pair of parallel guide members 43, 44 which are rigidly mounted on swing plate 1.

Means are provided for adjustment of the spacing between successive pleats comprising an adjustment screw 46 mounted in a threaded block 47 secured to the swing plate 1. The end of the adjustment screw turnsin an opening in the depending flange of an angle bracket 48 which is connected to adjustment plate 37 by bolts 49. When the screw 46 is rotated, plate 37 carrying the cylinder 34, the slide plate 31 and head 11 move together as a unit until the desired position of adjustment is reached, as indicated by a pleat space scale 51 mounted on the plate 37. This adjustment determines the position of the head in its fully extended position which it occupies at the beginning and at the end of the operating cycle (see FIG. 12) and thus determines the distance between the pleater and the long stitch line at the time when the pleater closes to form a pleat.

The head 11 is pivotally mounted on the bracket 32 to swing on a horizontal axis which is parallel to the plane of blade 13 and perpendicular to the axis of the cylinder 34. For this purpose, ball joints 55 and 56 are mounted on posts 57 and 58 mounted near the ends of the bracket 32, said ball joints having shanks 59 and 60 which are fixed in the head 11.

Means are also provided for controlling the depth of the pleats, which said means are adjustable to permit the pleat depth to be changed as desired. In the embodiment herein desribed means are also provided for automatically and simultaneously adjusting the amplitude of pivotal movement of the head 11 on the ball joints 55, 56. As will be understood, the greater the pleat depth, the greater the take-up of material required to form the pleats, and the greater the pivotal movement required for the head. For this purpose, as shown in FlGS. 8-10, a cam disk is provided which is located in a recess 66 in the head 11, said disk having a shaft 67 which extends through cover plate 68. A dial 69 and an operating knob 70 are mounted on the shaft outside of the cover plate.

The camdisk has two peripheral cam surfaces 71 and 72 separated by a groove 73. Cam surface 71 controls pleat depth. Cam surface 72 controls the amplitude of tilt of the head 11. Preferably the cam surfaces are stepped, as shown, With each step having a correlated number on the dial 69 to indicate to the operator the pleat depth for which the machine is adjusted. A pin 75 is mounted on the cross bar 21 in position to engage the cam surface 71 as the head is moved downwardly when actuated by cylinder 23. An adjustable pin 76 extends through a flange 77 of bracket 78 which is bolted to the bracket 32. Flange 77 extends beneath the head 11 to a position such that the pin 76 engages the cam surface 72.

The operation of the machine is illustrated diagrammatically in FIGS. 12 to 23. Prior to beginning of a pleating operation, the stop 29 is adjusted to insure that the swing plate 1 is properly located as previously explained. At the beginning of a pleating operation, the operator first adjusts the machine for the pleat spacing desired by loosening the lock knob 53 to permit operation of the adjusting screw 46 to move the plate 37 to the desired position as indicated by the scale 51. The operator then adjusts for the desired pleat depth by turning the knob 70 to the proper position as indicated by the dial 69. FIGS. 12 and 13 illustrate the position of the parts at the beginning of a pleating operation. Before any pleats are formed, the operator places the fabric 80 on the feed plate with the leading transverse edge 81 against the back gauge 10 and the longitudinal edge 82 against the side gauge 9 and depresses an operating pedal (not shown) to clamp the fabric against the feed plate. Further depression of the pedal starts the stitching operation to form an L-shaped line of stitching of the pattern indicated. As the stitching operation proceeds, the feed plate first swings in counterclockwise direction, as shown in FIG. 14, while the operator, maintaining a slight tension on the fabric in the longitudinal direction, gradually moves the longitudinal edge into the pleater between the blades 13, 14 and 1S and the pleater channel 20. Stitching continues until the feed plate reaches the end of its counterclockwise motion, at which time the needle is at the corner of the stitch pattern as shown in P16. 16. At this time also, the longitudinal edge has reached the guide 26, and the feed plate has moved to a position such that the long line of stitching is parallel with the blade 13. Shortly before the feed plate reaches this position, the cylinder 23 and piston are activated to move the pleater channel downwardly, so that by the time the feed plate reaches this position the pleater channel 20 has completed its downward movement to close the pleater and form the first pleat 83. Meanwhile, as the pleater closes, the head 11 tilts on the ball joints 55, 56, as shown in FIG. 17 so that the pleat may be formed without applying excess tension to the fabric-between the pleater and the needle.

Heretofore it has been necessary for the operator to provide slack in the material between the pleater and the needle by manual manipulation of the material prior to the closing of the pleater, an operation which required long training to acquire the necessary skill to provide sufficient slack-on the one hand while avoiding an excess of slack on the other. It also involved some danger to the operator. Unskillful or careless operation frequently resulted in requiring a stopping of the stitching operation with resulting loss of time and efficiency.

Now, as shown in FIGS. 18 and 19, the feed plate moves forwardly toward the pleater to form the short line of stitching while at the same time, the pleater is actuated by the piston 33 to advance the pleater toward the feed plate to form slack in the fabric as indicated at 84. While the pleater remains in its advanced position, the short line of stitching is completed, after which the feed plate moves backwardly to double the short line, then swings in clockwise direction, as shown in FIGS. 20 and 22, to double the long line of stitching. As this occurs, the operator grasps the newly formed pleat 83 and at the same time pinches the hinged blades together as shown in FIG. 21. The operator then begins to strip the pleat by sliding it lengthwise of the pleater.

By the time the feed plate reaches. the end of its clockwise movement and the needle reaches the end of the long line of stitching (see FIG. 22), so that the stitched fabric can be released and removed from the feed plate, the newly formed pleat 83 will have been completely stripped from the pleater and will then be placed on the feed plate by the operator in position to be clamped and stitched during the next operating cycle. Meanwhile the pleater will have been retracted to its original position by operation of the piston 33.

It will be understood that the invention may be variously modified and embodied within the scope of the subjoined claims.

I claim as my invention:

1. A pleat forming attachment for sewing machines comprising a slide plate, a pleating head, a pleater channel cooperating with said head, means connecting said pleating head to said slide plate, a fixed pleater blade mounted on said head, a pair of movable blades hingedly mounted on said head on opposite sides of .said fixed blade to swing onv axes parallel to said fixed blade, means for reciprocating said slide plate and said pleating head along a path which is perpendicular to the plane of said fixed blade, and means for pivotally mounting said pleating head on said connecting means for tilting movement on a horizontal axis which is below said fixed blade and parallel to the plane of said fixed blade and perpendicular to the reciprocating movement of said slide plate to provide uniform slack along the fixed pleater blade during pleat forming.

2. A pleat forming attachment as claimed in claim 1 including means for adjusting the rest position of said head relative to said connecting means.

3. A pleat forming attachment as claimed in claim 1 said pleater channel being inverted U-shaped, means for mounting said channel on said head for reciprocating movement with respect thereto to move said channel into and out of pleat forming relation with said blades.

4. A pleat forming attachment as claimed in claim 3 including means for adjusting the amplitude of said reciprocating movement to thereby adjust the depth of said pleats.

- 5. A pleat forming attachment as claimed in claim 4 including means for adjusting the rest position of said head relative to said connecting means.

6. A pleat forming attachment as claimed in claim 5 in which said adjusting means include a cam disk having two separated peripheral cam surfaces, and means for rotating said cam disk on an axis perpendicular to the plane of said fixed blade to simultaneously adjust the depth of said pleats and the rest position of said head relative to said connecting means.

7. A pleat forming attachment as claimed in claim 1 including a fixed base plate, a swing plate pivotally mounted thereon, an adjustment plate slidably mounted on said swing plate, and means for adjusting the position of said adjustment plate with respect to said swing plate to thereby adjust the amplitude of said reciprocating movement to thereby control the distance between said successive pleats.

8. A pleat forming attachment as claimed in claim 7 including means for locking said adjustment plate in a desired position of adjustment.

9. A pleat forming attachment as claimed in claim 7 including a stop mounted on said base plate, resilient means to hold said swing plate against said stop, and means to adjust the position of said stop on said base plate. I 

1. A pleat forming attachment for sewing machines comprising a slide plate, a pleating head, a pleater channel cooperating with said head, means connecting said pleating head to said slide plate, a fixed pleater blade mounted on said head, a pair of movable blades hingedly mounted on said head on opposite sides of said fixed blade to swing on axes parallel to said fixed blade, means for reciprocating said slide plate and said pleating head along a path which is perpendicular to the plane of said fixed blade, and means for pivotally mounting said pleating head on said connecting means for tilting movement on a horizontal axis which is below said fixed blade and parallel to the plane of said fixed blade and perpendicular to the reciprocating movement of said slide plate to provide uniform slack along the fixed pleater blade during pleat forming.
 2. A pleat forming attachment as claimed in claim 1 including means for adjusting the rest position of said head relative to said connecting means.
 3. A pleat forming attachment as claimed in claim 1 said pleater channel being inverted U-shaped, means for mounting said channel on said head for reciprocating movement with respect thereto to move said channel into and out of pleat forming relation with said blades.
 4. A pleat forming attachment as claimed in claim 3 including means for adjusting the amplitude of said reciprocating movement to thereby adjust the depth of said pleats.
 5. A pleat forming attachment as claimed in claim 4 including means for adjusting the rest position of said head relative to said connecting means.
 6. A pleat forming attachment as claimed in claim 5 in which said adjusting means include a cam disk having two separated peripheral cam surfaces, and means for rotating said cam disk on an axis perpendicular to the plane of said fixed blade to simultaneously adjust the depth of said pleats and the rest position of said head relative to said connecting means.
 7. A pleat forming attachment as claimed in claim 1 including a fixed base plate, a swing plate pivotally mounted thereon, an adjustment plate slidably mounted on said swing plate, and means for adjusting the position of said adjustment plate with respect to said swing plate to thereby adjust the amplitude of said reciprocating movement to thereby control the distance between said successive pleats.
 8. A pleat forming attachment as claimed in claim 7 including means for locking said adjustment plate in a desired position of adjustment.
 9. A pleat forming attachment as claimed in claim 7 including a stop mounted on said base plate, resilient means to hold said swing plate against said stop, and means to adjust the position of said stop on said base plate. 